Video Experimental Relacionado

Updated: Nov 1, 2025

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Published on: July 30, 2017

Ingreso modular a las tetrahidrobenzo[b]azepinas funcionalizadas a través de la catálisis cooperativa

Xin Liu¹, Jianchun Wang^1,2, Guangbin Dong¹

¹Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.

Journal of the American Chemical Society

|June 23, 2021

Resumen

Este estudio presenta un nuevo método catalizado con paladio/norborneno para la síntesis de tetrahidrobenzo[b]azepinas (THBA) a partir de yoduros de arilo. Un nuevo norborneno sustituido por C7 permite una síntesis eficiente de diversos derivados de THBA y compuestos relacionados.

Área de la Ciencia:

Química orgánica
Catálisis
Química medicinal

Sus antecedentes:

Las tetrahidrobenzo[b]azepinas (THBA) son frecuentes en las moléculas bioactivas.
La síntesis modular de THBA funcionalizados es actualmente un desafío.

Objetivo del estudio:

Desarrollar un método sencillo y modular para la síntesis de THBA.
Explorar la utilidad de la catálisis cooperativa de paladio/norboraneo para la construcción de heterociclos de siete miembros.

Principales métodos:

Síntesis directa de THBA a partir de yoduros de arilo mediante catálisis cooperativa de paladio y norboreno (Pd/NBE).
Se utilizó un reactivo de aminas electrófilas atado a la olefina para la ortoaminación y la ciclización Heck 7-exo-trig.
Desarrolló un NBE sustituido por C7 (N1) para abordar los desafíos con ioduros de arilo orto-no sustituidos.

Principales resultados:

Logró una síntesis directa de THBA y otros compuestos de anillo de siete miembros benzo.
Demostró el papel crucial del grupo C7-bromo en N1 para promover las etapas catalíticas clave y estabilizar los intermedios.
Se ha aplicado con éxito el método en una síntesis simplificada de tolvaptan y diversos derivados de THBA.

Conclusiones:

El nuevo sistema catalítico Pd/NBE ofrece un enfoque versátil para la síntesis de THBA.
Las ideas mecánicas sobre el papel del grupo C7-bromo pueden guiar el diseño futuro del catalizador.
El método desarrollado proporciona acceso a andamios THBA farmacéuticamente relevantes y análogos sustituidos por C6.

Más Videos Relacionados

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

Published on: February 27, 2017

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Published on: September 18, 2016

Videos de Conceptos Relacionados

Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions

Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions

Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...

Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism

Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism

Birch reduction uses solvated electrons as reducing agents. The reaction converts benzene to 1,4-cyclohexadiene. The reaction proceeds by the transfer of a single electron to the ring to form a benzene radical anion. This anion is highly basic—it abstracts a proton from the alcohol to form a cyclohexadienyl radical. Another single electron transfer gives the cyclohexadienyl anion. A proton transfer from the alcohol forms 1,4-cyclohexadiene. Since this reduction occurs via radical anion...

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.

Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation

Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation

Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...

Nucleophilic Aromatic Substitution: Elimination–Addition

Nucleophilic Aromatic Substitution: Elimination–Addition

Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions, such as high temperatures or strong bases. The mechanism of substitution under such conditions involves the highly unstable and reactive benzyne intermediate. Benzyne contains equivalent carbon centers at both ends of the triple bond, each of which is equally susceptible to nucleophilic attack. This 50–50 distribution of products is...

Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

Robinson annulation is a base-catalyzed reaction for the synthesis of 2-cyclohexenone derivatives from 1,3-dicarbonyl donors (such as cyclic diketones, β-ketoesters, or β-diketones) and α,β-unsaturated carbonyl acceptors. Named after Sir Robert Robinson, who discovered it, this reaction yields a six-membered ring with three new C–C bonds (two σ bonds and one π bond).